Generally, in mining, miners must install and remove hangers from the ceiling of the mines. These hangers support various types of cables and wires, electrical and otherwise, etc. Often these hangers and cables are installed and removed by hand. Historically, to remove the cables, miners walked beneath the hangers and removed the cable from each hanger, or removed the cable and the hanger from the ceiling of the mine. All of this is and has been done by hand.
A Mobile Roof Support (“MRS”) is a machine used to perform full pillar extraction methods in underground coalmines. The use of MRS's eliminates the setting of roadway, turn, and breaker posts that are required during pillar recovery operations. These machines provide more effective ground control than timbers, and their usage enhances the safety of persons in the mines and reduces material handling injuries. MRS's are shield-type hydraulic support units mounted on crawler tracks and remotely controlled.
Many MRS's are equipped to retract cable and to wind up the cable. Often, though, even when minors are working with MRS's, the miners need to release the cable from the hangers by hand before the MRS can wind the cable. A need exists for miners working MRS's to be able to remove the cable from the roof supports or hangers while avoiding danger to miners working in the area of the so-called Red Zone Pillar Line (the “Red Zone”) in a mine.
The Red Zone is where the pillars of coal are being extracted. Miners are encumbered and endangered in their work by having to enter the Red Zone in order to retrieve the cable from the hangers. They are endangered by the possibility of the roof falling on top of them. A collapsible hanger, such as that shown by the present invention, would release the cable safely from the roof without miners having to enter the Red Zone to get the cable out of the hangers by hand. A collapsible roof hanger satisfies this need by allowing the cable to fall to the ground when tension and/or weight is put on the hanger, such as when the cable is retracted. Depending upon the embodiment of the hanger, it may or may not stay in the roof plate after the cable is released. In a preferred embodiment of the present invention, the hanger stays in the roof plate after releasing the cable. Additionally, the present invention collapsible hanger may be made in a variety of ways, which allow it to be produced and to sell at a low or reasonable cost. The low cost permits miners to leave the hangers in the mine instead of having to recover them to use for new mining projects and areas.